sustaining groundwater irrigation economies:
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Sustaining Groundwater Irrigation Economies:
China’s Challenge and Global Experience
Explosive Growth in Groundwater Use
• Powerful manifestation of growing water scarcity;
• Meteoric growth after 1960• Of the 1000 km3 /year of global groundwater
use, over 800 km3 in agriculture; 600 in South Asia and North China;
• Of the 300 m ha of global irrigation, over 1/3rd is from groundwater wells.
• Protecting groundwater is critical for future supply of domestic water needs.
Four Groundwater Socio-Ecologies (GwSEs)
Habitat-Support GwSEsWhere: Most cities, towns and villagesDriver: Population Density and IndustryChallenge: Depletion; Land Subsidence; Pollution
Non-Renewable GwSEsWhere: Arid and Semi-arid Regions; MENA; NubianDriver: Urban Growth and AgricultureChallenge: Planned utilization of a nonrenewable resource
Wealth-Creating GwSEsWhere: Western US; Israel; Turkey; Spain; S. Africa; Morocco; TunisiaDriver: Industrial, High-value AgricultureChallenge: Depletion; Drying up of wetlands and streams; Non-point pollution
Livelihoods-Support GwSEsWhere: India, Pakistan, Nepal, Bangladesh, North China plainsDriver: Small-holder subsistence Agriculture Challenge: Sustaining massive livelihoods and protecting the resource
Danger zone
Growth in Population Density around the world (people/km2) , 1700 – 1990
Source: International Institute of Applied Systems Analysis (IIASA)
Contrary to popular notion,
population growth over past 300
years occurred in semi-arid areas..
Expanding Cropland 1700-1990Fraction of grid cell in croplands
Source: International Institute of Applied Systems Analysis (IIASA)
Because surface irrigation occurs in river valleys, we often think that gw irrigation too would concentrate in
regions of abundant recharge..
Source: Döll, P., Lehner, B., Kaspar, F. (2002): Global modeling of groundwater recharge. In Schmitz, G.H. (ed.): Proceedings of Third International Conference on Water Resources and the Environment Research, Technical University of Dresden, Germany, ISBN 3-934253-17-2, Vol. I, 27-31
Long-term average groundwater recharge
GW intensification has had little to do with resource Endowments; but with Population pressure..
MalthusVersus
Boserup
Growth in groundwater use in selected countries
(author's estimates)
0
50
100
150
200
250
300
1940 1950 1960 1970 1980 1990 2000 2010
cub
ic k
m/y
ear
US
W.Europe
Spain
Mexico
China
India
Pakistan
Bangladesh
Sri Lanka
Vietnam
Ghana
South Africa
Tunisia
North China farmers have drastically increased their
groundwater use
Groundwater irrigated area in countries with intensive groundwater use in agriculture (FAO Aquastat 2003 and
other sources)
0.00
5000.00
10000.00
15000.00
20000.00
25000.00
30000.00
Azerb
aija
n
Peru
Nepal
Egypt
Philippin
es
Kore
a, D
em
People
's
Iraq
South
Afr
ica
Tunis
ia
Uzbekis
tan
Kazakhsta
n
Afg
hanis
tan
Moro
cco
Arg
entina
Cuba
Yem
en
Japan
Bra
zil
Syrian A
rab R
epublic
Turk
ey
Saudi A
rabia
Mexic
o
Bangla
desh
Iran, Is
lam
ic R
ep o
f
Pakis
tan
US
A
Chin
a
India
000 h
a
According to FAO, gw irrigated area in India,
China, Pakistan, B’desh and Nepal together is larger
than anywhere else in the world...
Figure Top 20 Groundwater Irrigation Countries in the World (FAO AQUASTST 2003)
0
5000
10000
15000
20000
25000
30000
Ind
iaU
SA
Ch
ina
Pakis
tan
Iran
Ban
gla
desh
Mexic
oS
au
di
Italy
Tu
rkey
Syri
aB
razil
Lib
ya
Mo
rocco
Arg
en
tin
aC
ub
aY
em
en
Afg
han
ista
nE
gyp
tA
lgeri
aA
ustr
ali
aU
zb
ekis
tan
Tu
nis
iaIr
aq
So
uth
Ko
rea
Kazakh
sta
n
'000 h
a
0.05.0
10.015.0
20.025.0
30.035.0
40.045.0
%
Area under groundwater irrigation
% of farming area under groundwater irrigation
In sum, groundwater boom in Asia is driven by:
• Tubewell technology• High population pressure on land;• Semi-arid, monsoon climate• Green Revolution technology• Pump and tubewell technology• Failure of public irrigation systems• Electricity subsidies (in India, Mexico, Syria)
Country Annual groundwater
use (km3)
No of Agricultural
Ground-water
Structures (million)
Extraction/structure (m3/year)
% of population dependent directly or
indirectly on groundwater
irrigation
India 200-210 21 7900 55-60
Pakistan-Punjab 45 0.5 90000 60-65
China 75-90 3.5 21500 22-25
Iran 29 0.5 58000 12-18
Mexico 40 0.07 414285 5-6
USA 100 0.2 500,000 <1-2
Groundwater irrigation drives national and regional politics because it affects majority of
country’s population..
Beneficial impacts:• Biggest alleviator of rural poverty• Driver of agricultural productivity
growth• Spatial equity in access to irrigation• High water productivity• Socio-economic and political
stability• Mobilizes private capital
Negative Impacts.
• Groundwater depletion;• Increased pumping costs and energy use;• Drying up of lean season stream-flows and
wetlands;• Threat of Secondary salinization • Geo-genic contaminants: arsenic and
fluoride;
Informalization of Irrigation..
• In well-managed water economies, water users are mediated through formal water service providers; and self-supply is minimal.
• The groundwater boom has made some of Asia’s water economies highly informal. Most water users have little or no contact with public systems; so they are difficult to reach and regulate..
Reigning in the booming groundwater economy..
China’s new policy of ‘water withdrawal permits’ is designed to formalize groundwater irrigation economy..
Water saving technologies—drips and mulching-- are taking off in cotton and other crops..
To what extent will these ease aggregate pressure on China’s groundwater aquifers unclear.. Some argue only reducing irrigated areas will help.. But this will be difficult in the short run.
IWMI Assessment of Mexican Water Reforms
• ‘Concessions’: Water Rights and volumes assigned ; Tradable; COTAS
• Mexico has around 100,000 irrigation tubewells; despite that, monitoring concessions and penalizing violations has proved difficult;
• Doubtful if reforms have contained groundwater extraction
• Mexico is now turning to differential energy prices as a mechanism to penalize over-drafters.
Challenge of groundwater governance..
Banning private wells would be difficult to implement; crowd them out by improving public water supply
Regulating final users is difficult; facilitate mediating agencies to emerge, and regulate them. China has lessons to offer.
Pricing agricultural groundwater use is infeasible; instead, use energy pricing and supply to manage agricultural groundwater draft.
No alternative to improved supply side management: better rain-water capture and recharge, imported surface water in lieu of groundwater pumping.
Grow the economy, take pressure off land, formalize the water sector.
Transformation of Informal Water Economies with Overall Economic GrowthStage I:
Completely Informal
Stage II: Largely Informal
Stage III: Formalizing
Stage IV: Highly Formal Water
Industry
% of users in the formal sector
<5% 5-35% 35-75% 75-95%
Examples Sub-Saharan Africa
India, Pakistan, Bangladesh
Mexico, Thailand, Turkey, Eastern China
USA, Canada, Western Europe, Australia
Dominant mode of water service provision
Self-supply and informal mutual-help community institutions
Partial PublicProvisioning but self-supply dominates
Private-public provisioning; attempts to improve service and manage the resource
Rise of modern water industry; High Intermediation; self-supply disappears
Human, technical, financial resources used/km3 of water diversion
% of total water use self-supplied
Rural population as % of total
Cost of domestic water as % of per caput income
Cost of water service provision
Concerns of the Governments
Infrastructure creation in Welfare Mode
Infrastructure and Water services, especially in Urban areas in a welfare mode
Infrastructure and service in towns and villages; Cost recovery; Resource protection
Integrated mgt. of water infrastructure, service and resource; Resource protection
Institutional Arrangements
Self-help; mutual help and feudal institutions dominate
Informal Markets; Mutual help and community management institutions
Organized service providers; self-supply declines; informal institutions decline in significance
Self-supply disappears; all users get served by modern water industry.
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